1. Field of the Invention
The present invention relates to a system for splitting log sections. More particularly, the present invention relates to a hydraulic device coupled to a splitter box device. Most particularly, the present invention relates to a two-stage hydraulic device coupled to a two-stage splitter box device for splitting log sections into small pieces suitable for firewood.
2. Background Information
It is common practice to split logs into smaller pieces to provide firewood that burns readily. This task can be done manually using a mall to strike a wedge which splits the log, but this is labor intensive and requires physical strength and endurance. In recent years, hydraulic cylinders have been used to push a section of log against a stationary wedge to split the log section into smaller pieces. The simple wedge has been replaced by devices having multiple cutting edges to divide the log section into smaller pieces with a single stroke of the hydraulic cylinder. Although numerous variations on the cutting wedge, also termed a splitter box, have been developed, nearly all are subject to plugging and binding when attempting to split the log section into many smaller pieces in a single pass through the splitter box.
Some examples of inventions involving devices or systems for cutting and splitting logs for which patents have been granted include the following.
Connolly et al., in U.S. Pat. No. 4,286,638, describe a machine for cutting a log into a succession of pieces of predetermined length at a cutting station, moving the cut piece to a first splitting station, splitting the first cut piece at the first splitting station while the next piece is being cut at the cutting station, moving the next piece to a second splitting station, splitting the next piece at the second splitting station while a third piece is being cut at the cutting station, moving the third piece to the first splitting station, and splitting the third piece at the first splitting station while a fourth piece is being cut and so on. The production of split wood is thus substantially increased by the use of two splitters combined with means for moving the successively cut pieces alternately to the splitters.
In U.S. Pat. No. 4,353,401, Schilling discloses a method and apparatus for splitting a log substantially along the grain into a plurality of sector-shaped segments. The apparatus comprises at least one sector splitter ring having a plurality of blades, a support for locating the splitter ring in a log movement path, means for pushing the log axially along a log movement path, a rotating backplate for supporting one end of the log being pushed along, with the backplate adapted to tilt and allow the backplate-supported end of the log to rotate as the log is pushed through the splitter ring, and guide means adapted to retain the floating backplate in the log movement path. The process comprises forcing one end of a log axially against and through at least one splitting blade, the other end of the log being in contact with a backplate that can tilt, and permitting relative rotation between the log and the splitting blade so that a split occurring in the log from the splitting blade substantially tends to follow the grain in the log.
Barnes et al., in U.S. Pat. No. 4,371,020, describe a process for preparation of long wood strands. Long wood strands are required for the production of structural lumber products. These strands must be split, and a method of splitting logs into longitudinal-grain wood strands comprises the steps of radially splitting a log substantially along the grain of the log into a plurality of sector shaped segments, parallel splitting each of the sector shaped segments along the grain of the segments into a plurality of substantially parallel slabs, and further splitting each of the parallel slabs substantially along the grain of the slabs into a plurality of longitudinal-grain wood strands.
In U.S. Pat. No. 4,373,564, Heikkinen discloses a self-propelled and steerable wood processing system for converting a log into firewood wherein the wood processing system has a pick-up mechanism that can be advanced into a pile of logs to be cut with the pick-up mechanism rotatably mounted to permit placing a log on a log deck where it can be fed into a cutting and splitting mechanism for forming the log into firewood.
Sakraida, Jr., in U.S. Pat. No. 4,391,312, describes a log splitting head comprising a baseplate, first and second vertical cutting plates opposed and spaced from each other and mounted to and perpendicular with the baseplate, each including a cutting edge, a horizontal cutting plate mounted to and supported by the first and second cutting plates, and also including a cutting edge, and means for securing the baseplate to the main frame of a log splitting machine.
In U.S. Pat. No. 4,421,149, Barnes et al. disclose a process for making long wood strands. Long wood strands are required in structural lumber products and, in order to obtain maximum strength, should be split along the grain. A method of splitting a log into longitudinal-grain wood strands is disclosed comprising the steps of radially splitting the log substantially along the grain of the log into a plurality of sector shaped segments. Radial splitting includes pushing the log axially through at least one sector splitter ring, and further splitting the sector shaped segments substantially along the grain of the segments. The further splitting step includes feeding each of the sector shaped segments through two rows of intermeshing counter rotating discs, pulling each of the segments between the rows of discs and simultaneously splitting each of the segments into a plurality of longitudinal-grain wood strands.
Johnston, in U.S. Pat. No. 4,478,263, describes a mobile self-contained wood processing machine used for the processing of logs into specific lengths and then splitting the lengths into individual pieces suitable for use as firewood or the like. The individual pieces are retained in a unit bin until a desired quantity has been processed. Once the desired quantity is processed, the unit bin is operated to release the stored pieces to a handling cart or to packaging.
In U.S. Pat. No. 4,782,866, Valdez discloses a log splitting head, which includes a downwardly sloped top portion having a sharpened leading edge in the form of a V-shaped cutting blade. Beneath the top portion, a first row of vertical cutting blades is provided, each including a sharpened leading edge. Also included is a second row of vertical cutting blades beneath the first row of blades and structurally similar thereto. Separating the two rows of blades is a medial portion having a sharpened leading edge. The sides of the splitting head include two vertical plates having sharpened leading edges. All of these components are arranged in a specific angular configuration designed to accomplish log splitting with maximum efficiency. The entire unit is adapted for attachment to a horizontal platform and enables the splitting of logs into uniformly sized sections.
Nunnery et al., in a series of patents, including U.S. Pat. Nos. 4,829,865, 4,830,070, 4,834,154 and 4,869,303, describe a wood processor for cutting a log into a series of shorter lengths and subsequently splitting the shorter lengths into individual pieces of firewood or the like. The processor includes a carriage for receiving the log. Clamps engage the log from both sides to secure it in the carriage, which advances the log into contact with a plurality of parallel rotating saws. After the carriage is retracted, a pusher rod moves the cut log pieces along an axis onto a plurality of cradle members, one cradle supporting each log section. The cradle members are tilted to dump the log sections alternately onto opposite sides of the axis of log movement. The logs dumped from the cradles are fed to a plurality of individual hydraulically operated log splitters.
In U.S. Pat. No. 4,830,071, Gollahon discloses a wood stump splitting apparatus that includes a splitting chamber for receiving a plurality of various sized wood stumps. The splitting chamber has one wall including a splitter grid. Press is provided for pressing the wood stumps against cutting edges of the splitter grid and pushing the plurality of wood stumps through the splitter grid apertures. Press includes a plurality of longitudinal, spaced-apart pushing members, which push the stumps through grid apertures and ensure complete extrusion of wood pieces and prevent sticking of the compressed wood pieces in grid apertures.
Meyer, in U.S. Pat. No. 4,842,030, describes improvements in log splitting devices, including an improved log-lifting table having multiple attachment points and greater upward radial movement. A multiple-faceted splitting wedge is also disclosed, which has a cutting angle of less than 90 degrees and a splitting angle of greater than 90 degrees.
In U.S. Pat. No. 4,875,514, Hollister, Jr. discloses a method and an apparatus for performing the method, wherein a log of wood is split by being forced through a generally conical shaped apparatus, containing a multiplicity of uniquely shaped, spaced, interconnected, and cooperatively operative knives or splitting elements. The method involves forcing a large log of wood through the uniquely shaped knife, or splitting element, arrangement in such a manner that there is in effect a stepped splitting of the wood into relatively uniformly shaped pieces of wood suitable to be used for a variety of purposes including, but not limited to, firewood, and the like.
Hudson, in U.S. Pat. No. 4,961,452, describes a log splitting apparatus with a sensing mechanism arranged with adjustment linkages to vary the position of a cutter blade in accordance with the sensed diameter of a given log to-be-split. A sensing wheel is arranged to ride on the side of the log and is mounted on a pivotable arm, operatively connected to the cutter blade. The pivotable arm is connected to mechanical linkages, so as to automatically position a cutter assembly for producing the splitting of logs substantially in half. An optional multi-blade cutter assembly produces quartering of a log during a single log feeding operation.
U.S. Pat. No. 5,022,445 by Holestine discloses a double-acting hydraulic ram that drives a log section or block through a blade assembly to split the log section into several smaller pieces. The blade assembly is configured to minimize the force required to split the log section into several pieces without jamming. More specifically, the assembly includes a vertical blade having a splitting edge inclined rearward in the direction of movement of the block section toward the blade and horizontal wings cantilevered from the vertical blade. Each wing is swept outward and rearward from the vertical blade and has a leading edge staggered rearward from the splitting edge of the vertical blade. An exit conveyor is provided with a chain and flight members, driven solely by the reciprocating action of the ram for transporting the split pieces to a desired location.
In U.S. Pat. No. 5,284,193, Mires et al. disclose a log splitter having a first frame with a wedge fixedly attached thereto and extending outwardly therefrom. A carriage is mounted for reciprocation upon the first frame, and an abutment plate is attached to the carriage and extends outwardly therefrom in alignment with the wedge, so arranged to split a log between the abutment plate and the wedge. A hydraulic cylinder is present for reciprocating the abutment plate and carriage toward and away from the wedge, together with a second frame rotatably mounted to the first frame so that the first frame may rotate relative thereto about an axis. A hydraulic piston-and-cylinder is operably interposed between the first and second frames for rotating the first frame about its longitudinal axis. A log support cradle extends outwardly from the carriage, with rollers on the cradle to ease positioning of a log. The first frame rotates between a loading position, in which a log on the ground is gripped between the abutment plate and the wedge, and a splitting position, in which the log is split, with the log being lifted onto the splitter as the first frame rotates.
Smith, in U.S. Pat. No. 5,711,357, describes an adjustable, multi-wedge, splitting head for a log splitting apparatus equipped with a ram for axially advancing precut logs toward the splitting head in a horizontal direction. The apparatus includes a vertically oriented stationary post and a stationary triangular splitting wedge disposed between the post and the log to be split. The post holds upper and lower multiple splitting wedge assemblies, which can be slideably positioned on the post by hydraulic cylinder/piston units. The triangular splitting wedge severs a log into two pieces. The wedge assemblies then sever the initially produced two pieces into smaller pieces, the number of which corresponds to the number of blades in the assembly positioned to interact with the log.
In U.S. Pat. No. 5,791,389, Valdez discloses an apparatus and method for processing relatively large tree logs into relatively small firewood logs using two, spaced apart, cutting stations. The apparatus includes a central conveyor, a transfer station and a splitter station wherein relatively large tree logs are placed sequentially onto an entrance portion of each of the two spaced apart cutting stations and are cut into rounds, which are discharged onto the conveyor and moved to a transfer station. Each round is moved into a splitter station, wherein each round is moved over splitter blades to form firewood logs. The splitter blades are mounted in support members secured to a square frame, having spaced apart opposite sidewalls wherein the distance between each two aligned support members is greater than the distance between opposite sidewalls.
Fager, in U.S. Pat. No. 6,135,178, describes a device for splitting wood that comprises a rotatable and movable cutting device. A splitting blade is positioned on one end of the cutting device, which acts to split the wood when the cutting device is advanced in a direction toward the wood. The cutting device can be rotated to position the splitting blade with respect to the wood to facilitate the desired splitting of the wood. The cutting device is positioned on a positioning carriage, which is moved with respect to the wood that is to be split. The positioning carriage is movably positioned on a moveable carriage to further assist in positioning the splitting blade with respect to the wood to effectively and efficiently split the wood.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not necessarily to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention., as defined by the appended claims.